Connective device for electrical conduits and the like.



A. MDMURTRIE. OONNEOTIVE DEVICE FOR ELECTRICAL commrrs AND THE LIKE.

APPLICATION FILED DBO.13,1907.

Patented Mar. 30, 1909.

Swuenfoz 3513 1M 6 H0144 c1 cz/mm UNITED STATES PATENT, OFFICE.

ADNAH MCMURTRIE, OF NEW YORK, N. Y.,, ASSIGNOR TO THOMAS d: BETTS COMPANY, OF

' NEW YORK, N. Y., A CORPORATION OF NEW YORK.

OONNEOTIVE DEVICE FOR ELEGTRICAI- OOIIDUITB AND THE w.

Specification of Letters Patent.

Patented ma so, 1909.

Application filed December 18, 1901. Serial llfo. 408,861.

To all whom it may concern:

Be it known that I, ADNAH Mclilum'nm, of New York, N. Y., have invented certain Improvements in Connective Devices for Electrical Conduits and the Like, of which the 'following description, in connection with the accompanying drawings, is a specification, like numerals on the drawings designating like parts.

This invention relates to electrical conduit and particular] to the connectors or bushings used at t e ends of armor tubes. or sheaths to provide a smooth exit for the conductors, and used also to couple or connect adjacent conduit members, whether a plurality of sheaths or a sheath and another {)orm of conduit member such as an outlet By the term sheath as used hereinafter I intend to designate any form of tubular member, whether formed as a unitary structure with the conductor, as in the so called armored conductors or having a separate identity as in the various forms of armor conduit, or other tubular members.

. The expense of providing sheaths with screw threads, the cost of threaded fittings the expensive labor re uired to install threaded connectors, and t e lack of adaptability of threaded connections to numerous types of sheaths in general use, have made a universal, threadless coupling a desideratum, but many of the devices advanced to .meet this need have failed to rovide for the requisite rip upon thc'sheat s necessary to secure V mec anic'al union, and the abrasive engagement oi the conduit members requisite to insure electrical connection, while such connective devices as set screws normal to the of the sheath have proved too periphe l an expedient in the hands of the powerfu average workman, and sheaths have beenlectod for illustration and .plete understanding) tion, without recourse to threaded unions or destructive set screws normal to the sheaths.

Another important object of m invention is so to construct the connective evice as to facilitate its application to sheaths in situations where the use of threaded unions would be diflicult to effect, as by reason of the inadequacy of the projecting sheath-end to receive a die for the formation of a screw thread of sufiicient length to hold a coupling, or where the rotation of one or'more of the members is rendered diflicult or impossible by their angular relation to each other, or their confined situation, and in many other instances which occur fre uently in the daily ex erience of those skilled in the art.

its preferred form my invention con sists of an attachment or sheaths provided with an abutment to be supported near the periphery of the sheath, and between which and the sheath pla s a binding member, with means to force the bindi member into wedging relation with the utment and sheath, thus connecting them mechanically, and preferably electrically.

The'various features of my invention will be illustrated and described fully in the accom anying drawings' and speci cation and poin ted out in the c aims.

In the drawings, Figure I shows in side elevation, partly in section, an outlet box of well-known form, and in place thereon a number of connectors in the construction of which my invention has been embodied; Fig. 2 shows in vertical section a similar conhector a lied to the projecting stub of a pipe too ort to receive an a equatescrew thread; Fig. 3 is a double connector of the t shown in Fig. 2; and Fig. 4 is a view in 31 e elevation of my improved connector in use to connect a sheath and elbow.

In the embodiment of m invention se escription as a convenient form to enable ready and comof my improvements the part designated y the reference numera 1 is an abutment which in accordance with my invention in its referred form 1s suported near the sheet 2 to which m novel ttachment is to be secured and whic in the instance illustrated is constituted by the orpirail wound tubular metallic sheath a we -known form of armored conductor, the reierence numerals 3 and 4 designating the wall, and preferabl conductors and their insulation respectively. The support of the abutment may be provided by any suitable means and as one convenient form of such means I have shown a housing 5 to receive and surround the end of the sheath 2, forming a seat therefor, the abutment 1 being in this case formed integrally with the housin as a ortion of its s ightly inclined reladiameter of the sheath. The sheath 2 fits somewhat loosel in the seat 5, and to secure the sheath an attachment together firmly I provide a binding member 6 to lay between the abutment 1 and the sheat 2; also an actuating member or means 7 to force the binding member into binding engagement with the sheath and abutment respectively, the binding member 6 and means just described com risin in the instance illustrated a stove bo t 0 which 6 is the nut constituting the binding member and 7 the draft screw constituting the actuatin member, the shank of the latter passing t rough a hole 8 in a shoulder 9 formed in the wall of the housing to serve as a base for the screw head 10.

In operation, the screw is rotated to the right and draws'the binding member 6 into the conver ing pocket formed b the abutment and t e neighborin wall 0 the sheath 2 such being the stren th of the draft exerused that the nut 6, ri ing upon the inclined abutment 1, is forced over against the sheath 2 and crowds the latter into bindingengagement with the seat 5, the nut also cutting into the eriphery of the sheath and makin electrica connection betweenthe sheath and the housing, when as I prefer the housing is made of metal. a

In Fig. 1, the attachments are shown in osition to secure sheaths to the walls 11 am 12 of an electrical outlet box, and to facilitate such unions the attachments are illustrated as having integral attaching ortions 13 reduced in diameter to enter t e usual apertures 14 and having threaded necks 15 on which are seated retainin nuts 16, while 17 is a rounded rotective oulder to prevent abrasion of t e insulation of a conductor.

The length of contact between nut 6 and the sheath not only affords an am 1e surface for binding engagement but also istributes the strain and prevents puncture or deformation of the sheath byt a nut, a characteristic fault accompanyin the use of set screws normal to the peripk cry of the sheath when applied by an uns il ustrates an instance where this extended re ion of engagement affords means to grip e ciently a ve pipe below a cei ing 19, no op ortunity being given here to work a screw t reading die on the ipe end. S ecial coupling devices have been utilized eretofore in connection with such pipe stubs, but these devices have tively to the vertica illed workman. Fig. 2.

short projecting stub 18 of r been complicated in construction and unsatisfactory in operation. In. this re, 20 designates a female threaded attaching neck or portion toreceive the threaded end of a pipe, and 21 designates a rounded protective shoulder to prevent abrasion of the conductor led therethrough, the whole forming a very compact, neat housing with the operating parts accessible but unobtrusive. The abutment is desi ated in this figure by the reference numera 22, while 23 refers to the bindin member 24 to the draft screw, and 25 to the seat, all similar to parts already described under the same names.

I have illustrated at the right hand side of the outlet box in Fig. 1 two instances where the direction from which the sheath approaches the box is a factor that renders difcult the connection of the sheath to the box by the ordinary devices available, but this connection can be readily effected by means of the special forms of connective devices shown in Fig. 1 and in the construction of which my invention has been embodied.

In the instance of the attachment desi nated b the reference numeral 26 the nec to whic that numeral refers is bent to present the mouth of the housing 27 at an angle of about 45 to the axis of the aperture 28 in the bottom 29 of the box, to which the attachingpo'rtion 30 of the device is secured by a nut 31, the abutment 32, bolt 33 and nut 34' corresponding exactl in construction to the similar parts alrea y described. It is obvious that no attachment requiring rotative application to the sheath 35 coul be secured in place as conveniently as by the means em odied in my novel connective device, which makes possible the an ularly arranged fitting illustrated. A similar fitting is shown at 36 where the curvature amounts to 90 and the advantage is still more marked. In this fitting the seat portion 37 is elongated considerabl to allow for less accurate termination o the sheath 38, as the degree of entrance of the sheath within the housing does not affect the ease and efficiency with which the nut 39 is drawn by the bolt 40 against theabutment 41 and into engagement with the sheath 38 as already described with reference to the other forms of my device. The shoulder 42, attaching neck 43 and retaining nut 44 are also similar to like parts alread described.

Fig. 3 shows a cubic connector or couplin comprising an elongated body 45 at each en of w ich is formed a housin with a seat 46 and abutment 47, the draw olts 48 and nuts 49 serving in the scribed to hold in place the ends of sheaths (not shown), while a medial protective shoulder 50 may be provided to prevent abrasion of conductors in passing from one sheath to the other. The a earance of the coupling shown in Fig. 3, i t e same be rotated 180,

I cially 21 about its longitudinal axis, and then viewed to an article, such as an electrical conduit from left to right, is similar to the a armember, having a curved surface; said de-. ance of the device near the center of ig. 1 vice comprising a screw; means to support bearing numerals 110 inclusive. Ifdesired said screw in transverse relat on to said IS the interior of one or both ends may be made curved member; and an engaging member of spiral contour as at 51 in conformitz with arranged to be moved tangentia y into bindthe spiral exteriors of the sheaths w en so ing engagement with said curved surface by constructed. the rotation of said screw; substantially as In F i 4, I have illustrated a fitting espedescribed. 7

do. ted for use in situations where it 3.'Means to secure a device of the class is desirab e to draw a conductor outward described upon a tubular member, said axially rather than around a bend, this fitmeans com rising a screw supported loosely ting resembling in general contour that upon said evice near the periphery of said shown at the extreme right of Fig. 1, but tube, and a nut on said screw and movable 15 applied to cou la a screw threaded'arriior by the rotation thereof into binding engage-'80 e 52 to a exible armor tube 53 at an ment with said periphery angle of 90. In accordance with my inven- 4. Attaching means 0 the class described; ,tion the elbow 54 is rovided witha removcomprising a screw;'a nut thereon; and able cap 55 securer by suitable fastenin means to an port said screw and nut a ja- 20 means over an oval a erture 56 throng cent the pat oi the article with which atwhich right lineor axia access may be had tachment is to be effected, to permit transto the tubes 52 and 53. In the instance verse tangential traversal by said nut of a illustrated the fastening means takes the portion of said ath, upon, and by means of, form of a screw-bolt 62, passing through the rotation of sai screw to move said nut into 25 cap lug 64, and elbow lug 65, respectivel binding engagement with said article to The tube 52 is shown as screwe direct y couple to other said article and attaching into the elbow at 66, while the tube 53 1s means; so stantially as described.

rovided with an attachment of the form 5. A device of the class described; comfirst herein described and which is cou led prising a housing to receive the end of a so to the threaded end 67 of the elbow 54 y a sheath and provided with a lateral abutment short ring or coupling 68. Other forms of for the purpose set forth; a nut lying within connective devices may be utilized as desaid housing and against said abutment; sired and found suitable with my improved and means to force said nut between said elbow. abutment and said sheath to engage said 35 Having illustrated and described my insheath and clamp said device and sheath vention thus fully and suitable means for together substantially as described. carrying the same into effect, it willbe un- 6. A device of the class described; comderstood that I do not limit myself to the prising a housing to receive the end of a specific materials nor to the specific forms sheath and provi ed with a lateral abutment 4'0 0 trated, nor in general otherwise than as set said housing and against said abutment; forth in the claims, read in connection with and a draft screw operable from outside said this specification. housing, to force said nut between said S ecific claims upon the form of structure abutment and said sheath, to engage said 45 illustrated in Fig. 2, and those at the right sheath and clamp said device and sheath hand side of Fig. 1, will be found in my aptogether; substantially as described.

plication Ser. No. 451,940, the sub'ect mat 7. A device of the class described; comter of which has been divided rom this prising a housin to receive the end of a present application. I sheath and provi ed with a lateral abutment 50 What claim and desire to secure by for the purpose set forth; a nut lying within Letters Patent 1s: said housing and against said abutment;

1. Attaching means of the class described; and means to force said nut between said comprising an actuating member;-a bindabutment and said sheath, to bring an edge ing member thereon; means to support said of said nut into longitudinal engagement as actuating member and binding member with the periphery of said sheath, to cause adjacent the path of the article with which mechanical and electrical attachment of said attachment is to be eiiected, to permit device and sheath. transverse, tangential traversal by said 8. Acoupling device of the class described; binding member of a portion of'said 'ath,, com rising a tubular housing to receive the 60 upon, and bymeans of, movement 0 said artio es to be coupled and provided near actuating member to move said binding each end with a lateral abutment; a pluralmember into binding engagement with sai it of nuts, one for, and lying. against, each article, to couple together said article and 0 said abutments; and draft-screws for said attaching means; substantially as described. nuts respectively, to force the same between 65 2. A binding device to secure attachment said abutments and articles to engage the construction herein described and illus for the purpose set forth; a nut lying within 105 latter and clamp the saine in coil led relation with said housing; substantia y as described.

9. A coupling device of the class described comprising a tubular housing to receive at each end a tubular sheath and having a lat;- eral abutment adjacent each sheath-receiving portion; nuts lying against said abutments respectively; and draft-screws to u forcesaidnuts respectively between their abutments and sheaths to engage and clamp said sheaths in place, and to couple the same together said housing having an inner medial s oulder of less diameter than'the bore of said sheaths; substantially as de- 15 scribed. 4

Signed at New York in the count and State of New York this eighteenth (ay of November, 3907.

ADNAH MOMURTRIE.

Witnesses:

R. F. HARRXSON, H. E. OGLE. 

